Grout brush



FIG. 1 is a perspective view of grout brush showing our new design;

FIG. 2 is a right-hand view thereof, the left-hand view being a mirror image;

FIG. 3 is a top view thereof;

FIG. 4 is a front view thereof; and,

FIG. 5 is a back view thereof.

The broken lines showing bristles illustrate portions of the grout brush that form no part of the claimed design. 

The ornamental design for grout brush, as shown and described. 